Head Rush Ajax

70

Chapter 2

Break Neck Pizza, Ajax-style

Instead of starting with old 1990s development ideas, let’s look at what the Break

Neck app should do. Then you can use your new asynchronous programming skills

to make sure Break Neck’s order form is a responsive, customer-friendly means of

getting great pizza, fast. Here’s how things should work:

Yeah, come on over, the pizza’s

already here. Unbelievable... it can’t

have been ten minutes, and I didn’t

even have to enter my address.

The customer starts

out by entering his

phone number.

The order form then lls in the

customer’s address automatically.

Once the customer has

entered in his order, he

clicks “Order Pizza”...

...and Alex, the delivery

boy, can get the hot

pizza right to the

customer’s front door.

The customer enters their

pizza order into the form,

without waiting on their

address to get lled in.

an asynchronous approach

you’re on your way 4

71

ajax requests

Just like the Boards ‘R’ Us application in Chapter 1, you’re going to

need several JavaScript functions to make the Break Neck app work.

Below on the left are the names of two JavaScript functions, and on

the right are several lines of JavaScript. Draw arrows from the lines

of code to the function each line of code should go into.

getCustomerInfo()

updatePage()

if (request.readyState == ...